Question: $ { \left[\begin{array}{rrr}{4} & {-2} & {-1} \\ {4} & {1} & {0}\end{array}\right]-\left[\begin{array}{rrr}{0} & {1} & {-1} \\ {-2} & {0} & {-1}\end{array}\right] = {?} } $
To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{4}-{0} & {-2}-{1} & {-1}-{-1} \\ {4}-{-2} & {1}-{0} & {0}-{-1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{4} & {-3} & {0} \\ {6} & {1} & {1}\end{array}\right]}$